On the Regulation of the Respiration in Reptiles

1961 ◽  
Vol 38 (2) ◽  
pp. 301-314 ◽  
Author(s):  
BODIL NIELSEN
Keyword(s):  
Steady State ◽  
Body Temperature ◽  
Metabolic Rate ◽  
Temperature Interval ◽  
Normal Values ◽  
Pulmonary Ventilation ◽  
The Body ◽  
Respiratory Frequency ◽  
Temperature Changes ◽  
Instantaneous Increase

1. In two species of Lacerta (L. viridis and L. sicula) the effects on respiration of body temperature (changes in metabolic rate) and of CO2 added to the inspired air were studied. 2. Pulmonary ventilation increases when body temperature increases. The increase is brought about by an increase in respiratory frequency. No relationship is found between respiratory depth and temperature. 3. The rise in ventilation is provoked by the needs of metabolism and is not established for temperature regulating purposes (in the temperature interval 10°-35°C). 4. The ventilation per litre O2 consumed has a high numerical value (about 75, compared to about 20 in man). It varies with the body temperature and demonstrates that the inspired air is better utilized at the higher temperatures. 5. Pulmonary ventilation increases with increasing CO2 percentages in the inspired air between o and 3%. At further increases in the CO2 percentage (3-13.5%) it decreases again. 6. At each CO2 percentage the pulmonary ventilation reaches a steady state after some time (10-60 min.) and is then unchanged over prolonged periods (1 hr.). 7. The respiratory frequency in the steady state decreases with increasing CO2 percentages. The respiratory depth in the steady state increases with increasing CO2 percentages. This effect of CO2 breathing is not influenced by a change in body temperature from 20° to 30°C. 8. Respiration is periodically inhibited by CO2 percentages above 4%. This inhibition, causing a Cheyne-Stokes-like respiration, ceases after a certain time, proportional to the CO2 percentage (1 hr. at 8-13% CO2), and respiration becomes regular (steady state). Shift to room air breathing causes an instantaneous increase in frequency to well above the normal value followed by a gradual decrease to normal values. 9. The nature of the CO2 effect on respiratory frequency and respiratory depth is discussed, considering both chemoreceptor and humoral mechanisms.

On the Regulation of Respiration in Reptiles

1962 ◽  
Vol 39 (1) ◽  
pp. 107-117
Author(s):  
BODIL NIELSEN
Keyword(s):  
Body Temperature ◽  
Metabolic Rate ◽  
Pulmonary Ventilation ◽  
Respiratory Frequency ◽  
Regulation Of Respiration ◽  
Combined Effects ◽  
O2 Uptake ◽  
Lacerta Viridis ◽  
Increased Sensitivity ◽  
Respiratory Apparatus

The effects of various degrees of hypoxia and the combined effects of hypoxia and moderate hypercapnia (2·8% CO2 in the inspired air) have been studied in seven specimens of Lacerta viridis (green lizard) and three of Tarentola mauretanica (gecko). 1. It was found that hypoxia reduces the O2 uptake. 2. Pulmonary ventilation was little changed by hypoxia until the O2% of the inspired air was reduced below 10, when it decreased. 3. A small increase in the ratio (pulmonary ventilation/hr.)/(O2 uptake/hr.) with decreasing O2% was found. When CO2 was added to the O2 mixtures the increase was much greater, indicating an increased sensitivity of the respiratory apparatus towards CO2 during hypoxia. 4. The effect of hypoxia on respiratory frequency was always to cause a decrease. Addition of 2·8% CO2 to the inspired air had little effect. At a body temperature of 20°C. the decrease occurred at O2% in the inspired air below 10, whereas at 30°C. the frequency was higher, but decreased as soon as the O2% was below 20 (room air). 5. It was found that the respiratory frequency in Lacerta varies linearly with the metabolic rate (O2 uptake). 6. The respiratory depth increases with decreasing O2% in the inspired air, at 20°C. below 10% O2 and at 30°C. below 20% O2. Addition of 2·8% CO2 in both cases doubled the respiratory depth at all degrees of hypoxia.

TEMPERATURE REGULATION IN EXERCISE

PEDIATRICS ◽  
1963 ◽  
Vol 32 (4) ◽  
pp. 691-702
Author(s):  
Sid Robinson
Keyword(s):  
Blood Flow ◽  
Body Temperature ◽  
Heat Stroke ◽  
The Body ◽  
Physiological Regulation ◽  
Temperature Changes ◽  
Metabolic Heat ◽  
Warm Blood ◽  
Hot Environments ◽  
Large Increments

The central body temperature of a man rises gradually during the first half hour of a period of work to a higher level and this level is precisely maintained until the work is stopped; body temperature then slowly declines to the usual resting level. During prolonged work the temperature regulatory center in the hypothalamus appears to be reset at a level which is proportional to the intensity of the work and this setting is independent of environmental temperature changes ranging from cold to moderately warm. In hot environments the resistance to heat loss may be so great that all of the increased metabolic heat of work cannot be dissipated and the man's central temperature will rise above the thermostatic setting. If this condition of imbalance is continued long enough heat stroke will ensue. We have found that in a 3 mile race lasting only 14 minutes on a hot summer day a runner's rectal temperature may rise to 41.1°C., with heat stroke imminent. The physiological regulation of body temperature of men in warm environments and during the increased metabolic heat production of work is dependent on sweating to provide evaporative cooling of the skin, and on adjustments of cutaneous blood flow which determine the conductance of heat from the deeper tissues to the skin. The mechanisms of regulating these responses during work are complex and not entirely understood. Recent experiments carried out in this laboratory indicate that during work, sweating may be regulated by reflexes originating from thermal receptors in the veins draining warm blood from the muscles, summated with reflexes from the cutaneous thermal receptors, both acting through the hypothalamic center, the activity of which is increased in proportion to its own temperature. At the beginning of work the demand for blood flow to the muscles results in reflex vasoconstriction in the skin. As the body temperature rises the thermal demand predominates and the cutaneous vessels dilate, increasing heat conductance to the skin. Large increments in cardiac output and compensatory vasoconstriction in the abdominal viscera make these vascular adjustments in work possible without circulatory embarrassment.

Extracellular and intracellular carbon dioxide concentration as a function of temperature in the toad Bufo marinus.

1994 ◽  
Vol 195 (1) ◽  
pp. 345-360 ◽  
Author(s):  
J N Stinner ◽  
D L Newlon ◽  
N Heisler
Keyword(s):  
Body Temperature ◽  
Extracellular Fluid ◽  
Carbon Dioxide Concentration ◽  
The Body ◽  
Whole Body ◽  
Mean Values ◽  
Temperature Changes ◽  
Fluid Compartment ◽  
Average Change ◽  
Higher Temperature

Previous studies of reptiles and amphibians have shown that changing the body temperature consistently produces transient changes in the respiratory exchange ratio (RE) and, hence, changes in whole-body CO2 stores, and that the extracellular fluid compartment contributes to the temperature-related changes in CO2 stores. The purpose of this study was to determine whether the intracellular fluid compartment contributes to the changes in CO2 stores in undisturbed resting cane toads. Increasing body temperature from 10 to 30 degrees C temporarily elevated RE, and returning body temperature to 10 degrees C temporarily lowered RE. The estimated average change in whole-body CO2 stores associated with the transient changes in RE was 1.0 +/- 0.8 mmol kg-1 (+/- S.D., N = 6). Plasma [CO2] and, thus, extracellular fluid [CO2], were unaffected by the temperature change. Plasma calcium levels were also unaffected, so that bone CO2 stores did not contribute to changes in whole-body CO2 stores. Intracellular [CO2] was determined for the lung, oesophagus, stomach, small intestine, liver, ventricle, red blood cells, skin and 14 skeletal muscles. [CO2] was significantly lower (P < 0.05) at higher temperature in 10 of these, and seven others, although not statistically significant (P > 0.05), had mean values at least 0.5 mmol kg-1 lower at the higher temperature. The average change in intracellular [CO2] for all tissues examined was -0.165 mmol kg-1 degrees C-1. We conclude that, in cane toads, the temperature-related transients in RE result from intracellular CO2 adjustments, that different tissues have unique intracellular CO2/temperature relationships, and that a combination of respiratory and ion-exchange mechanisms is used to adjust pH as temperature changes.

The metabolic rate and thermal conductance of the eastern barred bandicoot (Perameles gunnii) at different ambient temperatures

2003 ◽  
Vol 51 (6) ◽  
pp. 603 ◽  
Author(s):  
M. P. Ikonomopoulou ◽  
R. W. Rose
Keyword(s):  
Oxygen Consumption ◽  
Body Temperature ◽  
Metabolic Rate ◽  
Thermal Conductance ◽  
The Body ◽  
High Metabolic Rate ◽  
Ambient Temperatures ◽  
Reduced Body ◽  
Thermoneutral Zone ◽  
Reproductive Females

We investigated the metabolic rate, thermoneutral zone and thermal conductance of the eastern barred bandicoot in Tasmania. Five adult eastern barred bandicoots (two males, three non-reproductive females) were tested at temperatures of 3, 10, 15, 20, 25, 30, 35 and 40°C. The thermoneutral zone was calculated from oxygen consumption and body temperature, measured during the daytime: their normal resting phase. It was found that the thermoneutral zone lies between 25°C and 30°C, with a minimum metabolic rate of 0.51 mL g–1 h–1 and body temperature of 35.8°C. At cooler ambient temperatures (3–20°C) the body temperature decreased to approximately 34.0°C while the metabolic rate increased from 0.7 to 1.3 mL g–1�h–1. At high temperatures (35°C and 40°C) both body temperature (36.9–38.7°C) and metabolic rate (1.0–1.5 mL g–1 h–1) rose. Thermal conductance was low below an ambient temperature of 30°C but increased significantly at higher temperatures. The low thermal conductance (due, in part, to good insulation, a reduced body temperature at lower ambient temperatures, combined with a relatively high metabolic rate) suggests that this species is well adapted to cooler environments but it could not thermoregulate easily at temperatures above 30°C.

scholarly journals Refinement of Temperature Sensing Yarns

Proceedings ◽  
2017 ◽  
Vol 2 (3) ◽  
pp. 123 ◽  
Author(s):  
Pasindu Lugoda ◽  
Tilak Dias ◽  
Theodore Hughes-Riley ◽  
Rob Morris
Keyword(s):  
Thermal Properties ◽  
Steady State ◽  
Body Temperature ◽  
Temperature Monitoring ◽  
Temperature Sensing ◽  
Temperature Measurements ◽  
Wound Infections ◽  
Temperature Changes ◽  
Additional Information ◽  
Polymer Resin

Body temperature is an important parameter to measure in a number of fields such as medicine and sport. In medicine temperature changes can indicate underlying pathologies such as wound infections, while in sport temperature can be associated to a change in performance. In both cases a wearable temperature monitoring solution is preferable. In earlier work a temperature sensing yarn has been developed and characterized. The yarns were constructed by embedding an off-the-shelf thermistor into a polymer resin micro-pod and then into the fibers of a yarn. This process created a temperature sensing yarn that was conformal, drapeable, mechanically resilient, and washable. This work builds on this early study with the purposes of identifying the steady state error bought about on the temperature measurements as a result of the polymer resin and yarn fibers. Here a wider range of temperatures than previously explored were investigated. Additionally two types of polymer resin with different thermal properties have been tested, with varying thicknesses, for the encapsulation of the thermistor. This provides useful additional information for optimizing the temperature sensing yarn design.

scholarly journals Heart rate reveals torpor at high body temperatures in lowland tropical free-tailed bats

2017 ◽  
Vol 4 (12) ◽  
pp. 171359 ◽  
Author(s):  
M. Teague O'Mara ◽  
Sebastian Rikker ◽  
Martin Wikelski ◽  
Andries Ter Maat ◽  
Henry S. Pollock ◽  
...  
Keyword(s):  
Heart Rate ◽  
Body Temperature ◽  
Metabolic Rate ◽  
Ambient Temperature ◽  
The Body ◽  
Metabolic Rates ◽  
Body Temperatures ◽  
Wide Range ◽  
Save Energy ◽  
Molossus Molossus

Reduction in metabolic rate and body temperature is a common strategy for small endotherms to save energy. The daily reduction in metabolic rate and heterothermy, or torpor, is particularly pronounced in regions with a large variation in daily ambient temperature. This applies most strongly in temperate bat species (order Chiroptera), but it is less clear how tropical bats save energy if ambient temperatures remain high. However, many subtropical and tropical species use some daily heterothermy on cool days. We recorded the heart rate and the body temperature of free-ranging Pallas' mastiff bats ( Molossus molossus ) in Gamboa, Panamá, and showed that these individuals have low field metabolic rates across a wide range of body temperatures that conform to high ambient temperature. Importantly, low metabolic rates in controlled respirometry trials were best predicted by heart rate, and not body temperature . Molossus molossus enter torpor-like states characterized by low metabolic rate and heart rates at body temperatures of 32°C, and thermoconform across a range of temperatures. Flexible metabolic strategies may be far more common in tropical endotherms than currently known.

Body temperature and standard metabolic rate of the female viviparous lizard Eremias multiocellata during reproduction

2012 ◽  
Vol 90 (1) ◽  
pp. 79-84 ◽  
Author(s):  
Feng Yue ◽  
Xiao-Long Tang ◽  
De-Jiu Zhang ◽  
Xue-Feng Yan ◽  
Ying Xin ◽  
...  
Keyword(s):  
Body Temperature ◽  
Metabolic Rate ◽  
Ambient Temperature ◽  
Energy Cost ◽  
Energy Requirement ◽  
Standard Metabolic Rate ◽  
The Body ◽  
Energetic Cost ◽  
Pregnant Females ◽  
Eremias Multiocellata

The body temperature (Tb) and standard metabolic rate (SMR) of female Eremias multiocellata Günther, 1872, a viviparous lizard, were measured at 25, 30, and 35 °C during pregnancy and after parturition to assess energy requirement of reproduction. The results showed that the Tbs of female lizards were slightly higher than actual ambient temperature in the 25 and 30 °C groups, while they were slightly lower than ambient temperature in the 35 °C group. Ambient temperature significantly affected SMR and gestation period of females. Energy requirement was constant in nonpregnant females, whereas it was increased in pregnant females. The maximal estimates of maintenance costs of pregnancy (MCP) were 4.219, 4.220, and 4.448 mg CO2·min–1, which accounted for 19.40%, 14.15%, and 12.32% of the total metabolic rate in the 25, 30, and 35 °C group, respectively. The results indicated the MCP was an important component of total energy cost for the lizard E. multiocellata and the MCP in this lizard incurs a relative fixed energetic cost irrespective of ambient temperature.

scholarly journals Printable, Highly Sensitive Flexible Temperature Sensors for Human Body Temperature Monitoring: A Review

2020 ◽  
Vol 15 (1) ◽  
Author(s):  
Yi Su ◽  
Chunsheng Ma ◽  
Jing Chen ◽  
Huiping Wu ◽  
Weixiang Luo ◽  
...  
Keyword(s):  
Body Temperature ◽  
Human Body ◽  
High Sensitivity ◽  
Measurement Range ◽  
Temperature Sensors ◽  
Temperature Monitoring ◽  
The Body ◽  
Temperature Changes ◽  
Practical Applications ◽  
Highly Sensitive

Abstract In recent years, the development and research of flexible sensors have gradually deepened, and the performance of wearable, flexible devices for monitoring body temperature has also improved. For the human body, body temperature changes reflect much information about human health, and abnormal body temperature changes usually indicate poor health. Although body temperature is independent of the environment, the body surface temperature is easily affected by the surrounding environment, bringing challenges to body temperature monitoring equipment. To achieve real-time and sensitive detection of various parts temperature of the human body, researchers have developed many different types of high-sensitivity flexible temperature sensors, perfecting the function of electronic skin, and also proposed many practical applications. This article reviews the current research status of highly sensitive patterned flexible temperature sensors used to monitor body temperature changes. First, commonly used substrates and active materials for flexible temperature sensors have been summarized. Second, patterned fabricating methods and processes of flexible temperature sensors are introduced. Then, flexible temperature sensing performance are comprehensively discussed, including temperature measurement range, sensitivity, response time, temperature resolution. Finally, the application of flexible temperature sensors based on highly delicate patterning are demonstrated, and the future challenges of flexible temperature sensors have prospected.

Hibernation in the Eastern Pygmy Possum, Cercartetus-Nanus (Marsupialia, Burramyidae)

1993 ◽  
Vol 41 (1) ◽  
pp. 67 ◽  
Author(s):  
F Geiser
Keyword(s):  
Oxygen Consumption ◽  
Body Temperature ◽  
Metabolic Rate ◽  
Air Temperature ◽  
The Body ◽  
Daily Torpor ◽  
Rate Of Oxygen Consumption ◽  
The Mean ◽  
Cercartetus Nanus ◽  
Torpor Bouts

The pattern of torpor was examined in the eastern pygmy possum, Cercartetus nanus (21 g). Animals displayed torpor regularly in the laboratory, and the occurrence of torpor increased with decreasing air temperature (T(a)). At high T(a) (18-degrees-C) animals usually exhibited daily torpor, but torpor bouts of up to 2 days were observed occasionally. The duration of torpor bouts lengthened with a lowering of T(a) and the mean bout duration at T(a) = 5-degrees-C was 17.0 +/- 2.5 days. The minimum metabolic rate (measured as rate of oxygen consumption) of torpid individuals was 0.018 +/- 0.003 mL O2 g-1 h-1, which is less than 2% of the basal metabolic rate. The body temperature (T(b)) Of torpid animals fell to a minimum of 1.3 +/- 0.4-degrees-C. These results clearly demonstrate that Cercartetus nanus is a deep hibernator.

THE EFFECT OF HIGH HUMIDITY ON BODY TEMPERATURE AND OXYGEN CONSUMPTION OF NEWBORN PREMATURE INFANTS

PEDIATRICS ◽  
1961 ◽  
Vol 27 (5) ◽  
pp. 740-747
Author(s):  
Herbert C. Miller ◽  
Franklin C. Behrle ◽  
David L. Hagar ◽  
Terry R. Denison
Keyword(s):  
Oxygen Consumption ◽  
Body Temperature ◽  
Relative Humidity ◽  
Premature Infants ◽  
Normal Values ◽  
The Body ◽  
High Humidity ◽  
Body Temperatures ◽  
Initial Decrease ◽  
Consistent Increase

Relative humidity between 80 and 90% increased the body temperatures of both healthy and sick premature infants, the increase being greatest in the least mature infants. No significant, consistent increase in oxygen consumption was observed to accompany the increase in body temperature produced by high relative humidity. Low relative humidity between 20 and 60% did not prevent the return of body temperature to normal values after the initial decrease immediately following birth. The return to normal was slower in the less mature infants. Low relative humidity was not incompatible with the survival of very small premature infants maintained in an ambient temperature betwen 88 and 90°F (31.1 to 32.2°C).

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